1. Field of the Invention:
The present invention relates to a device for cutting brushwood containing bushes, shrubs and the like, as well as other vegetation. The brushwood cutting device is advantageously mounted on the distal end of a multiple-joint backhoe operated through hydraulic cylinders to form a hydraulic powered arm of balance cutter device.
2. Background of the Invention:
One of the longstanding problems in forestry industries, road maintenance, large and small-scale farming, high voltage transportation line cleaning, etc, has been to control the undersirable shrubs, bushes and the like (brushwood). It has been experienced that the conventional cutting devices are not practical for the purpose of cutting such brushwood.
A first example of conventional cutter device is illustrated and described in U.S. Pat. No. 3,319,407 (Jordan et al.) issued on May 16, 1967. As shown in FIG. 17 of this patent, a pair of superposed bars are rotated through a driving shaft. At the opposite ends of the two bars are mounted respective blades through two diametrically opposed pivots. If the cutter device of Jordan et al. is used to cut brushwood, the bars hit the bushes, shrubs, and the like and break. Obviously, the cutter device of U.S. Pat. No. 3,319,407 is not structured to cut brushwood.
A second example of conventional cutter device is proposed in FIG. 3 of U.S. Pat. No. 4,506,464 (Cartner) issued on Mar. 26, 1985. The device of Cartner comprises as illustrated in FIG. 3 a light-weight rotating disk on the periphery of which are fixedly attached cutter blades. If used for cutting brushwood, the blades hit the larger bushes and shrubs, and eventually other obstacles such as stumps, and these blades and possibly the light-weight disk are damaged. The life of the device of U.S. Pat. No. 4,506,464 is accordingly very short when used in cutting brushwood. Moreover, due to the light-weight design of the rotating disk of Cartner, its inertia is low and the rotational speed is greatly influenced by any shock between the blades and the brushwood, whereby the efficiency of the device in cutting brushwood is obviously reduced by a rotational speed widely varying in time.
It can further be easily appreciated by one skilled in the art that the housing proposed in each of the above-mentioned U.S. Pat. Nos. 3,319,407 and 4,506,464 is not adapted to carry out cutting of brushwood including bushes, shrubs and the like.